There is a need to produce higher density powder metal parts. There are ways of coating or adding thin lubricants or polymer coatings as interfaces between the particles which decreases the internal friction and stresses created during compaction.
Some problems have arisen with different types of heating devices for powder metal. When heated to a temperature of about 300 degrees Fahrenheit before loading the material into the die cavity, the powder may become tacky and coagulate. Typical powder delivery systems have used mechanical devices; these systems have some drawbacks. Mechanical devices will cause some coagulating or snowballing of the powder due to tacky lube being rolled over and over. Air fluid beds will segregate the material due to sizes, weight variations in particles. Pleated hoses will allow material to gather in pleats and block the hose.
Since the usual production method requires accurate gravity controlled filling of the die cavity from the delivery shoe, the present invention designs around these known problems.